Method of making propeller blades



Oct. 25 1932 I Q J, SQUIIRESII 1,884,903

I lis'mon or MAKING PROPELLER BLADES Fill 9d D86. 9, 1929 Ill/17111111111111]! A. IIIIIIIIIIIIII ATTORNEYS.

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Patented Oct. 2 5, 1932 UNITED STATES PATENT ore-E 101m saumns; or naenasrown, MARYLAND METHOD OF MAKING PBOPELLER BLADES Application filed December 9, 1929. Serial No; 412,670.

This invention relates to a method of formin hollow, seamless steel propeller blades. be main objects of this invention are to provide an-improved method of forming a by the use of which an exceptionally highgrade propeller blade maybe constructed at a relatively low cost. I a

An illustrative embodiment of this in- "vention is shown in the accompanying drawig. 1 isan edge view of the disc-shaped blank from which the propeller blade is made.

Fig. 2 is a plan view of the same.

Fig. 3 is a sectional view showing the first air of drawing dies after the first draw has een made of the blank.

Fig. 4 is a similar view of the next pair of drawing dies after the next draw of the metal.

Fig. 5 is a similar view-of the third pair of drawing dies after drawing the metal.

' Fig. 6 is a similar view showing the ta ered drawing dies after having drawn the lank '.to a substantially uniform taper throughout its length. Fig. 7 is a fragmentary sectional view of the swaging dies after having formed the head around the open 'end of the base of the blank. I

Fig. 8 is a fragmentary sectional view showing the base bead after having been machined.

Fig. 9 is a thin sectional vlew showin the tubular blank in position between the ormin dies.

l i 10 is a similar view of the same after the Forming dies have pressed the tubular blank to an airfoil section.

In-the embodiment disclosed in the accompanying drawing a. disc-shaped blank of steel 11 is placed between a'pair of drawing dies 12 and 13 and the dies. closed, as shownin Fig. 3 of the drawing, so as to draw out the middle portion of. the blank to make it of shallow cup-shape.

The cup-shaped blank is then placed'between a second pair of drawing dies 14 and 15,

which draw out a smaller portion 16 of the blank, such portion being concentricwith respect to the original disc and the cup-shaped blank after the first draw.

The blank is then placed in another set of dies 17 and 18 which draw out a pro ressively smaller concentric portion 19 o the blank, thus causing the blank to bejstep- 1 shaped in longitudinal section, as shown in Figs. 4 and 5 of the drawing. This successive drawing of progressively smaller concentric portions is continued until the blank has assumed proper length, at which time, it is then subjected to the action of a pair of tapered dies 20 and 21 of circular cross section and having a substantially uniform taper from end to end. These dies form the blank into an elongated uniformly tapered tube 22 as shown in Fig. 6 of the drawing. The base or open end of the tube is then subjected to the action of a pair of swaging dies 23 and 24 which form an outwardly extendingannular flange or bead 25 around the open end of 0 the tube 22.

' The bead 25 is then machined to form a flange 26 as shown in Fig. 8 of the drawing, by which the finished propeller blade may be mounted in a suitable socket.

The tube 22 is then placedbetween a pair of forming dies 27 and 28 which have depressions 29 and 30 therein. The depressions 29 and 30 have the same perimetric measurement as the outer circumference of the tube 22 so that the tube will not be stretched during the forming operation/ The dies 27 and 28 are then brought together as shown in Fig. 10 of the drawing, thus changing the cross sectional shape of the tube from circular to an air- 95 foil section.

This forming operation is described more in detail in my copending application which bears Serial No. 334,876, filed January 25,

Although but one specific embodiment has been herein disclosed, it will be understood that numerous details thereof may be altered or omitted without departing from the spirit of this invention, as defined by the following claims.

I claim:

1. The method of forming a hollow, seam less metal propeller blade which comprises the subjecting of a disc-shaped blank successively t0 the action of a plurality of pairs of drawing dies, each pair of which draws out a progressively smaller concentric portion of the blank to make it substantially stepshape in longitudinal section, then subjecting the blank to the action of a pair of ta pered drawing dies, upsetting a bead around the open end of said blank, and then subjecting the blank to a pair of forming dies for pressing opposite sides of the tapered blank toward each other to secure the desired crosssectional shape.

2. The method of forming a hollow, seamless metal propeller blade which comprises the subjecting of a disc-shaped blank successively to the action of a plurality of pairs of drawing dies, each pair of which draws out a progressively smaller concentric portion of the blank to make it substantially step-shape in longitudinal section and having a closed outer end, then subjecting the blank to the action of a pair of tapered drawing dies, and then subjecting the blank to a pair of farming dies for pressing the tapered blank to an airfoil cross-section.

3. The method of forming a hollow, seamless metal propellerblade which comprises the subjecting of a disc-shaped blank successively to the action of a plurality of pairs of drawing dies, each pair of which draws out a progressively smaller concentric portion of the blank to make an elongated tubular structure of varying diameter and wall thickness having a closed outer end, then subjecting the blank to the action of a pair of tapered drawing dies of circular cross-section, and then subjecting the blank to a pair of forming dies for pressing the tapered tubular blank to an airfoil cross-section.

4. The method of forming a hollow, seamless propeller blade which includes subjecting a disc-shaped metal blank successively to rounded closed end and gradually tapering in diameter and wall thickness towards the closed end thereof, and squeezing said member between a pair of dies to form it into blade shape.

6. The method of forming a hollow, seamless propeller blade which includes subjecting a disc-shaped metal blank successively to the action of a plurality of drawing .dies whereby to form said blank into an elongated cup shaped member having a gradually rounded closed end and gradually tapering in diameter and diminishing in wall thickness toward the closed end thereof, forming a peripheral flange at the open end thereof, and then squeezing said member between dies to blade formation.

7. The method of forming a hollow, seamless propeller blade which includes subjecting a disc-shaped metal blank successively to the action of a plurality of drawing dies whereby to form said blank into an elongated cup shaped member having a gradually rounded closed end and gradually tapering in diameter and diminishing in wall thickness toward the closed end thereof, forming a peripheral flange at the open end thereof,,and then squeezing said member between dies to blade formation without circumferentially stretching said walls of said member.

JOHN SQUIRES.

the action of a plurality of drawing dies whereby to form said blank into an elongated cup shaped member gradually tapering in diameter and wall thickness towards the closed end thereof, and squeezing said member between a pair of dies to form it into blade shape.

5'. The method of forming a hollow, seamless propeller blade which includes subjecting a disc-shaped metal-blank successively to the action of a plurality of drawing dies whereby to form said blank into an elongated cup shaped member having a gradually 

